| /* |
| * core function to access sclp interface |
| * |
| * Copyright IBM Corp. 1999, 2009 |
| * |
| * Author(s): Martin Peschke <mpeschke@de.ibm.com> |
| * Martin Schwidefsky <schwidefsky@de.ibm.com> |
| */ |
| |
| #include <linux/kernel_stat.h> |
| #include <linux/module.h> |
| #include <linux/err.h> |
| #include <linux/spinlock.h> |
| #include <linux/interrupt.h> |
| #include <linux/timer.h> |
| #include <linux/reboot.h> |
| #include <linux/jiffies.h> |
| #include <linux/init.h> |
| #include <linux/suspend.h> |
| #include <linux/completion.h> |
| #include <linux/platform_device.h> |
| #include <asm/s390_ext.h> |
| #include <asm/types.h> |
| #include <asm/irq.h> |
| |
| #include "sclp.h" |
| |
| #define SCLP_HEADER "sclp: " |
| |
| /* Structure for register_early_external_interrupt. */ |
| static ext_int_info_t ext_int_info_hwc; |
| |
| /* Lock to protect internal data consistency. */ |
| static DEFINE_SPINLOCK(sclp_lock); |
| |
| /* Mask of events that we can send to the sclp interface. */ |
| static sccb_mask_t sclp_receive_mask; |
| |
| /* Mask of events that we can receive from the sclp interface. */ |
| static sccb_mask_t sclp_send_mask; |
| |
| /* List of registered event listeners and senders. */ |
| static struct list_head sclp_reg_list; |
| |
| /* List of queued requests. */ |
| static struct list_head sclp_req_queue; |
| |
| /* Data for read and and init requests. */ |
| static struct sclp_req sclp_read_req; |
| static struct sclp_req sclp_init_req; |
| static char sclp_read_sccb[PAGE_SIZE] __attribute__((__aligned__(PAGE_SIZE))); |
| static char sclp_init_sccb[PAGE_SIZE] __attribute__((__aligned__(PAGE_SIZE))); |
| |
| /* Suspend request */ |
| static DECLARE_COMPLETION(sclp_request_queue_flushed); |
| |
| static void sclp_suspend_req_cb(struct sclp_req *req, void *data) |
| { |
| complete(&sclp_request_queue_flushed); |
| } |
| |
| static struct sclp_req sclp_suspend_req; |
| |
| /* Timer for request retries. */ |
| static struct timer_list sclp_request_timer; |
| |
| /* Internal state: is the driver initialized? */ |
| static volatile enum sclp_init_state_t { |
| sclp_init_state_uninitialized, |
| sclp_init_state_initializing, |
| sclp_init_state_initialized |
| } sclp_init_state = sclp_init_state_uninitialized; |
| |
| /* Internal state: is a request active at the sclp? */ |
| static volatile enum sclp_running_state_t { |
| sclp_running_state_idle, |
| sclp_running_state_running, |
| sclp_running_state_reset_pending |
| } sclp_running_state = sclp_running_state_idle; |
| |
| /* Internal state: is a read request pending? */ |
| static volatile enum sclp_reading_state_t { |
| sclp_reading_state_idle, |
| sclp_reading_state_reading |
| } sclp_reading_state = sclp_reading_state_idle; |
| |
| /* Internal state: is the driver currently serving requests? */ |
| static volatile enum sclp_activation_state_t { |
| sclp_activation_state_active, |
| sclp_activation_state_deactivating, |
| sclp_activation_state_inactive, |
| sclp_activation_state_activating |
| } sclp_activation_state = sclp_activation_state_active; |
| |
| /* Internal state: is an init mask request pending? */ |
| static volatile enum sclp_mask_state_t { |
| sclp_mask_state_idle, |
| sclp_mask_state_initializing |
| } sclp_mask_state = sclp_mask_state_idle; |
| |
| /* Internal state: is the driver suspended? */ |
| static enum sclp_suspend_state_t { |
| sclp_suspend_state_running, |
| sclp_suspend_state_suspended, |
| } sclp_suspend_state = sclp_suspend_state_running; |
| |
| /* Maximum retry counts */ |
| #define SCLP_INIT_RETRY 3 |
| #define SCLP_MASK_RETRY 3 |
| |
| /* Timeout intervals in seconds.*/ |
| #define SCLP_BUSY_INTERVAL 10 |
| #define SCLP_RETRY_INTERVAL 30 |
| |
| static void sclp_process_queue(void); |
| static void __sclp_make_read_req(void); |
| static int sclp_init_mask(int calculate); |
| static int sclp_init(void); |
| |
| /* Perform service call. Return 0 on success, non-zero otherwise. */ |
| int |
| sclp_service_call(sclp_cmdw_t command, void *sccb) |
| { |
| int cc; |
| |
| asm volatile( |
| " .insn rre,0xb2200000,%1,%2\n" /* servc %1,%2 */ |
| " ipm %0\n" |
| " srl %0,28" |
| : "=&d" (cc) : "d" (command), "a" (__pa(sccb)) |
| : "cc", "memory"); |
| if (cc == 3) |
| return -EIO; |
| if (cc == 2) |
| return -EBUSY; |
| return 0; |
| } |
| |
| |
| static void |
| __sclp_queue_read_req(void) |
| { |
| if (sclp_reading_state == sclp_reading_state_idle) { |
| sclp_reading_state = sclp_reading_state_reading; |
| __sclp_make_read_req(); |
| /* Add request to head of queue */ |
| list_add(&sclp_read_req.list, &sclp_req_queue); |
| } |
| } |
| |
| /* Set up request retry timer. Called while sclp_lock is locked. */ |
| static inline void |
| __sclp_set_request_timer(unsigned long time, void (*function)(unsigned long), |
| unsigned long data) |
| { |
| del_timer(&sclp_request_timer); |
| sclp_request_timer.function = function; |
| sclp_request_timer.data = data; |
| sclp_request_timer.expires = jiffies + time; |
| add_timer(&sclp_request_timer); |
| } |
| |
| /* Request timeout handler. Restart the request queue. If DATA is non-zero, |
| * force restart of running request. */ |
| static void |
| sclp_request_timeout(unsigned long data) |
| { |
| unsigned long flags; |
| |
| spin_lock_irqsave(&sclp_lock, flags); |
| if (data) { |
| if (sclp_running_state == sclp_running_state_running) { |
| /* Break running state and queue NOP read event request |
| * to get a defined interface state. */ |
| __sclp_queue_read_req(); |
| sclp_running_state = sclp_running_state_idle; |
| } |
| } else { |
| __sclp_set_request_timer(SCLP_BUSY_INTERVAL * HZ, |
| sclp_request_timeout, 0); |
| } |
| spin_unlock_irqrestore(&sclp_lock, flags); |
| sclp_process_queue(); |
| } |
| |
| /* Try to start a request. Return zero if the request was successfully |
| * started or if it will be started at a later time. Return non-zero otherwise. |
| * Called while sclp_lock is locked. */ |
| static int |
| __sclp_start_request(struct sclp_req *req) |
| { |
| int rc; |
| |
| if (sclp_running_state != sclp_running_state_idle) |
| return 0; |
| del_timer(&sclp_request_timer); |
| rc = sclp_service_call(req->command, req->sccb); |
| req->start_count++; |
| |
| if (rc == 0) { |
| /* Successfully started request */ |
| req->status = SCLP_REQ_RUNNING; |
| sclp_running_state = sclp_running_state_running; |
| __sclp_set_request_timer(SCLP_RETRY_INTERVAL * HZ, |
| sclp_request_timeout, 1); |
| return 0; |
| } else if (rc == -EBUSY) { |
| /* Try again later */ |
| __sclp_set_request_timer(SCLP_BUSY_INTERVAL * HZ, |
| sclp_request_timeout, 0); |
| return 0; |
| } |
| /* Request failed */ |
| req->status = SCLP_REQ_FAILED; |
| return rc; |
| } |
| |
| /* Try to start queued requests. */ |
| static void |
| sclp_process_queue(void) |
| { |
| struct sclp_req *req; |
| int rc; |
| unsigned long flags; |
| |
| spin_lock_irqsave(&sclp_lock, flags); |
| if (sclp_running_state != sclp_running_state_idle) { |
| spin_unlock_irqrestore(&sclp_lock, flags); |
| return; |
| } |
| del_timer(&sclp_request_timer); |
| while (!list_empty(&sclp_req_queue)) { |
| req = list_entry(sclp_req_queue.next, struct sclp_req, list); |
| if (!req->sccb) |
| goto do_post; |
| rc = __sclp_start_request(req); |
| if (rc == 0) |
| break; |
| /* Request failed */ |
| if (req->start_count > 1) { |
| /* Cannot abort already submitted request - could still |
| * be active at the SCLP */ |
| __sclp_set_request_timer(SCLP_BUSY_INTERVAL * HZ, |
| sclp_request_timeout, 0); |
| break; |
| } |
| do_post: |
| /* Post-processing for aborted request */ |
| list_del(&req->list); |
| if (req->callback) { |
| spin_unlock_irqrestore(&sclp_lock, flags); |
| req->callback(req, req->callback_data); |
| spin_lock_irqsave(&sclp_lock, flags); |
| } |
| } |
| spin_unlock_irqrestore(&sclp_lock, flags); |
| } |
| |
| static int __sclp_can_add_request(struct sclp_req *req) |
| { |
| if (req == &sclp_suspend_req || req == &sclp_init_req) |
| return 1; |
| if (sclp_suspend_state != sclp_suspend_state_running) |
| return 0; |
| if (sclp_init_state != sclp_init_state_initialized) |
| return 0; |
| if (sclp_activation_state != sclp_activation_state_active) |
| return 0; |
| return 1; |
| } |
| |
| /* Queue a new request. Return zero on success, non-zero otherwise. */ |
| int |
| sclp_add_request(struct sclp_req *req) |
| { |
| unsigned long flags; |
| int rc; |
| |
| spin_lock_irqsave(&sclp_lock, flags); |
| if (!__sclp_can_add_request(req)) { |
| spin_unlock_irqrestore(&sclp_lock, flags); |
| return -EIO; |
| } |
| req->status = SCLP_REQ_QUEUED; |
| req->start_count = 0; |
| list_add_tail(&req->list, &sclp_req_queue); |
| rc = 0; |
| /* Start if request is first in list */ |
| if (sclp_running_state == sclp_running_state_idle && |
| req->list.prev == &sclp_req_queue) { |
| if (!req->sccb) { |
| list_del(&req->list); |
| rc = -ENODATA; |
| goto out; |
| } |
| rc = __sclp_start_request(req); |
| if (rc) |
| list_del(&req->list); |
| } |
| out: |
| spin_unlock_irqrestore(&sclp_lock, flags); |
| return rc; |
| } |
| |
| EXPORT_SYMBOL(sclp_add_request); |
| |
| /* Dispatch events found in request buffer to registered listeners. Return 0 |
| * if all events were dispatched, non-zero otherwise. */ |
| static int |
| sclp_dispatch_evbufs(struct sccb_header *sccb) |
| { |
| unsigned long flags; |
| struct evbuf_header *evbuf; |
| struct list_head *l; |
| struct sclp_register *reg; |
| int offset; |
| int rc; |
| |
| spin_lock_irqsave(&sclp_lock, flags); |
| rc = 0; |
| for (offset = sizeof(struct sccb_header); offset < sccb->length; |
| offset += evbuf->length) { |
| evbuf = (struct evbuf_header *) ((addr_t) sccb + offset); |
| /* Check for malformed hardware response */ |
| if (evbuf->length == 0) |
| break; |
| /* Search for event handler */ |
| reg = NULL; |
| list_for_each(l, &sclp_reg_list) { |
| reg = list_entry(l, struct sclp_register, list); |
| if (reg->receive_mask & (1 << (32 - evbuf->type))) |
| break; |
| else |
| reg = NULL; |
| } |
| if (reg && reg->receiver_fn) { |
| spin_unlock_irqrestore(&sclp_lock, flags); |
| reg->receiver_fn(evbuf); |
| spin_lock_irqsave(&sclp_lock, flags); |
| } else if (reg == NULL) |
| rc = -ENOSYS; |
| } |
| spin_unlock_irqrestore(&sclp_lock, flags); |
| return rc; |
| } |
| |
| /* Read event data request callback. */ |
| static void |
| sclp_read_cb(struct sclp_req *req, void *data) |
| { |
| unsigned long flags; |
| struct sccb_header *sccb; |
| |
| sccb = (struct sccb_header *) req->sccb; |
| if (req->status == SCLP_REQ_DONE && (sccb->response_code == 0x20 || |
| sccb->response_code == 0x220)) |
| sclp_dispatch_evbufs(sccb); |
| spin_lock_irqsave(&sclp_lock, flags); |
| sclp_reading_state = sclp_reading_state_idle; |
| spin_unlock_irqrestore(&sclp_lock, flags); |
| } |
| |
| /* Prepare read event data request. Called while sclp_lock is locked. */ |
| static void __sclp_make_read_req(void) |
| { |
| struct sccb_header *sccb; |
| |
| sccb = (struct sccb_header *) sclp_read_sccb; |
| clear_page(sccb); |
| memset(&sclp_read_req, 0, sizeof(struct sclp_req)); |
| sclp_read_req.command = SCLP_CMDW_READ_EVENT_DATA; |
| sclp_read_req.status = SCLP_REQ_QUEUED; |
| sclp_read_req.start_count = 0; |
| sclp_read_req.callback = sclp_read_cb; |
| sclp_read_req.sccb = sccb; |
| sccb->length = PAGE_SIZE; |
| sccb->function_code = 0; |
| sccb->control_mask[2] = 0x80; |
| } |
| |
| /* Search request list for request with matching sccb. Return request if found, |
| * NULL otherwise. Called while sclp_lock is locked. */ |
| static inline struct sclp_req * |
| __sclp_find_req(u32 sccb) |
| { |
| struct list_head *l; |
| struct sclp_req *req; |
| |
| list_for_each(l, &sclp_req_queue) { |
| req = list_entry(l, struct sclp_req, list); |
| if (sccb == (u32) (addr_t) req->sccb) |
| return req; |
| } |
| return NULL; |
| } |
| |
| /* Handler for external interruption. Perform request post-processing. |
| * Prepare read event data request if necessary. Start processing of next |
| * request on queue. */ |
| static void sclp_interrupt_handler(unsigned int ext_int_code, |
| unsigned int param32, unsigned long param64) |
| { |
| struct sclp_req *req; |
| u32 finished_sccb; |
| u32 evbuf_pending; |
| |
| kstat_cpu(smp_processor_id()).irqs[EXTINT_SCP]++; |
| spin_lock(&sclp_lock); |
| finished_sccb = param32 & 0xfffffff8; |
| evbuf_pending = param32 & 0x3; |
| if (finished_sccb) { |
| del_timer(&sclp_request_timer); |
| sclp_running_state = sclp_running_state_reset_pending; |
| req = __sclp_find_req(finished_sccb); |
| if (req) { |
| /* Request post-processing */ |
| list_del(&req->list); |
| req->status = SCLP_REQ_DONE; |
| if (req->callback) { |
| spin_unlock(&sclp_lock); |
| req->callback(req, req->callback_data); |
| spin_lock(&sclp_lock); |
| } |
| } |
| sclp_running_state = sclp_running_state_idle; |
| } |
| if (evbuf_pending && |
| sclp_activation_state == sclp_activation_state_active) |
| __sclp_queue_read_req(); |
| spin_unlock(&sclp_lock); |
| sclp_process_queue(); |
| } |
| |
| /* Convert interval in jiffies to TOD ticks. */ |
| static inline u64 |
| sclp_tod_from_jiffies(unsigned long jiffies) |
| { |
| return (u64) (jiffies / HZ) << 32; |
| } |
| |
| /* Wait until a currently running request finished. Note: while this function |
| * is running, no timers are served on the calling CPU. */ |
| void |
| sclp_sync_wait(void) |
| { |
| unsigned long long old_tick; |
| unsigned long flags; |
| unsigned long cr0, cr0_sync; |
| u64 timeout; |
| int irq_context; |
| |
| /* We'll be disabling timer interrupts, so we need a custom timeout |
| * mechanism */ |
| timeout = 0; |
| if (timer_pending(&sclp_request_timer)) { |
| /* Get timeout TOD value */ |
| timeout = get_clock() + |
| sclp_tod_from_jiffies(sclp_request_timer.expires - |
| jiffies); |
| } |
| local_irq_save(flags); |
| /* Prevent bottom half from executing once we force interrupts open */ |
| irq_context = in_interrupt(); |
| if (!irq_context) |
| local_bh_disable(); |
| /* Enable service-signal interruption, disable timer interrupts */ |
| old_tick = local_tick_disable(); |
| trace_hardirqs_on(); |
| __ctl_store(cr0, 0, 0); |
| cr0_sync = cr0; |
| cr0_sync &= 0xffff00a0; |
| cr0_sync |= 0x00000200; |
| __ctl_load(cr0_sync, 0, 0); |
| __arch_local_irq_stosm(0x01); |
| /* Loop until driver state indicates finished request */ |
| while (sclp_running_state != sclp_running_state_idle) { |
| /* Check for expired request timer */ |
| if (timer_pending(&sclp_request_timer) && |
| get_clock() > timeout && |
| del_timer(&sclp_request_timer)) |
| sclp_request_timer.function(sclp_request_timer.data); |
| cpu_relax(); |
| } |
| local_irq_disable(); |
| __ctl_load(cr0, 0, 0); |
| if (!irq_context) |
| _local_bh_enable(); |
| local_tick_enable(old_tick); |
| local_irq_restore(flags); |
| } |
| EXPORT_SYMBOL(sclp_sync_wait); |
| |
| /* Dispatch changes in send and receive mask to registered listeners. */ |
| static void |
| sclp_dispatch_state_change(void) |
| { |
| struct list_head *l; |
| struct sclp_register *reg; |
| unsigned long flags; |
| sccb_mask_t receive_mask; |
| sccb_mask_t send_mask; |
| |
| do { |
| spin_lock_irqsave(&sclp_lock, flags); |
| reg = NULL; |
| list_for_each(l, &sclp_reg_list) { |
| reg = list_entry(l, struct sclp_register, list); |
| receive_mask = reg->send_mask & sclp_receive_mask; |
| send_mask = reg->receive_mask & sclp_send_mask; |
| if (reg->sclp_receive_mask != receive_mask || |
| reg->sclp_send_mask != send_mask) { |
| reg->sclp_receive_mask = receive_mask; |
| reg->sclp_send_mask = send_mask; |
| break; |
| } else |
| reg = NULL; |
| } |
| spin_unlock_irqrestore(&sclp_lock, flags); |
| if (reg && reg->state_change_fn) |
| reg->state_change_fn(reg); |
| } while (reg); |
| } |
| |
| struct sclp_statechangebuf { |
| struct evbuf_header header; |
| u8 validity_sclp_active_facility_mask : 1; |
| u8 validity_sclp_receive_mask : 1; |
| u8 validity_sclp_send_mask : 1; |
| u8 validity_read_data_function_mask : 1; |
| u16 _zeros : 12; |
| u16 mask_length; |
| u64 sclp_active_facility_mask; |
| sccb_mask_t sclp_receive_mask; |
| sccb_mask_t sclp_send_mask; |
| u32 read_data_function_mask; |
| } __attribute__((packed)); |
| |
| |
| /* State change event callback. Inform listeners of changes. */ |
| static void |
| sclp_state_change_cb(struct evbuf_header *evbuf) |
| { |
| unsigned long flags; |
| struct sclp_statechangebuf *scbuf; |
| |
| scbuf = (struct sclp_statechangebuf *) evbuf; |
| if (scbuf->mask_length != sizeof(sccb_mask_t)) |
| return; |
| spin_lock_irqsave(&sclp_lock, flags); |
| if (scbuf->validity_sclp_receive_mask) |
| sclp_receive_mask = scbuf->sclp_receive_mask; |
| if (scbuf->validity_sclp_send_mask) |
| sclp_send_mask = scbuf->sclp_send_mask; |
| spin_unlock_irqrestore(&sclp_lock, flags); |
| if (scbuf->validity_sclp_active_facility_mask) |
| sclp_facilities = scbuf->sclp_active_facility_mask; |
| sclp_dispatch_state_change(); |
| } |
| |
| static struct sclp_register sclp_state_change_event = { |
| .receive_mask = EVTYP_STATECHANGE_MASK, |
| .receiver_fn = sclp_state_change_cb |
| }; |
| |
| /* Calculate receive and send mask of currently registered listeners. |
| * Called while sclp_lock is locked. */ |
| static inline void |
| __sclp_get_mask(sccb_mask_t *receive_mask, sccb_mask_t *send_mask) |
| { |
| struct list_head *l; |
| struct sclp_register *t; |
| |
| *receive_mask = 0; |
| *send_mask = 0; |
| list_for_each(l, &sclp_reg_list) { |
| t = list_entry(l, struct sclp_register, list); |
| *receive_mask |= t->receive_mask; |
| *send_mask |= t->send_mask; |
| } |
| } |
| |
| /* Register event listener. Return 0 on success, non-zero otherwise. */ |
| int |
| sclp_register(struct sclp_register *reg) |
| { |
| unsigned long flags; |
| sccb_mask_t receive_mask; |
| sccb_mask_t send_mask; |
| int rc; |
| |
| rc = sclp_init(); |
| if (rc) |
| return rc; |
| spin_lock_irqsave(&sclp_lock, flags); |
| /* Check event mask for collisions */ |
| __sclp_get_mask(&receive_mask, &send_mask); |
| if (reg->receive_mask & receive_mask || reg->send_mask & send_mask) { |
| spin_unlock_irqrestore(&sclp_lock, flags); |
| return -EBUSY; |
| } |
| /* Trigger initial state change callback */ |
| reg->sclp_receive_mask = 0; |
| reg->sclp_send_mask = 0; |
| reg->pm_event_posted = 0; |
| list_add(®->list, &sclp_reg_list); |
| spin_unlock_irqrestore(&sclp_lock, flags); |
| rc = sclp_init_mask(1); |
| if (rc) { |
| spin_lock_irqsave(&sclp_lock, flags); |
| list_del(®->list); |
| spin_unlock_irqrestore(&sclp_lock, flags); |
| } |
| return rc; |
| } |
| |
| EXPORT_SYMBOL(sclp_register); |
| |
| /* Unregister event listener. */ |
| void |
| sclp_unregister(struct sclp_register *reg) |
| { |
| unsigned long flags; |
| |
| spin_lock_irqsave(&sclp_lock, flags); |
| list_del(®->list); |
| spin_unlock_irqrestore(&sclp_lock, flags); |
| sclp_init_mask(1); |
| } |
| |
| EXPORT_SYMBOL(sclp_unregister); |
| |
| /* Remove event buffers which are marked processed. Return the number of |
| * remaining event buffers. */ |
| int |
| sclp_remove_processed(struct sccb_header *sccb) |
| { |
| struct evbuf_header *evbuf; |
| int unprocessed; |
| u16 remaining; |
| |
| evbuf = (struct evbuf_header *) (sccb + 1); |
| unprocessed = 0; |
| remaining = sccb->length - sizeof(struct sccb_header); |
| while (remaining > 0) { |
| remaining -= evbuf->length; |
| if (evbuf->flags & 0x80) { |
| sccb->length -= evbuf->length; |
| memcpy(evbuf, (void *) ((addr_t) evbuf + evbuf->length), |
| remaining); |
| } else { |
| unprocessed++; |
| evbuf = (struct evbuf_header *) |
| ((addr_t) evbuf + evbuf->length); |
| } |
| } |
| return unprocessed; |
| } |
| |
| EXPORT_SYMBOL(sclp_remove_processed); |
| |
| struct init_sccb { |
| struct sccb_header header; |
| u16 _reserved; |
| u16 mask_length; |
| sccb_mask_t receive_mask; |
| sccb_mask_t send_mask; |
| sccb_mask_t sclp_receive_mask; |
| sccb_mask_t sclp_send_mask; |
| } __attribute__((packed)); |
| |
| /* Prepare init mask request. Called while sclp_lock is locked. */ |
| static inline void |
| __sclp_make_init_req(u32 receive_mask, u32 send_mask) |
| { |
| struct init_sccb *sccb; |
| |
| sccb = (struct init_sccb *) sclp_init_sccb; |
| clear_page(sccb); |
| memset(&sclp_init_req, 0, sizeof(struct sclp_req)); |
| sclp_init_req.command = SCLP_CMDW_WRITE_EVENT_MASK; |
| sclp_init_req.status = SCLP_REQ_FILLED; |
| sclp_init_req.start_count = 0; |
| sclp_init_req.callback = NULL; |
| sclp_init_req.callback_data = NULL; |
| sclp_init_req.sccb = sccb; |
| sccb->header.length = sizeof(struct init_sccb); |
| sccb->mask_length = sizeof(sccb_mask_t); |
| sccb->receive_mask = receive_mask; |
| sccb->send_mask = send_mask; |
| sccb->sclp_receive_mask = 0; |
| sccb->sclp_send_mask = 0; |
| } |
| |
| /* Start init mask request. If calculate is non-zero, calculate the mask as |
| * requested by registered listeners. Use zero mask otherwise. Return 0 on |
| * success, non-zero otherwise. */ |
| static int |
| sclp_init_mask(int calculate) |
| { |
| unsigned long flags; |
| struct init_sccb *sccb = (struct init_sccb *) sclp_init_sccb; |
| sccb_mask_t receive_mask; |
| sccb_mask_t send_mask; |
| int retry; |
| int rc; |
| unsigned long wait; |
| |
| spin_lock_irqsave(&sclp_lock, flags); |
| /* Check if interface is in appropriate state */ |
| if (sclp_mask_state != sclp_mask_state_idle) { |
| spin_unlock_irqrestore(&sclp_lock, flags); |
| return -EBUSY; |
| } |
| if (sclp_activation_state == sclp_activation_state_inactive) { |
| spin_unlock_irqrestore(&sclp_lock, flags); |
| return -EINVAL; |
| } |
| sclp_mask_state = sclp_mask_state_initializing; |
| /* Determine mask */ |
| if (calculate) |
| __sclp_get_mask(&receive_mask, &send_mask); |
| else { |
| receive_mask = 0; |
| send_mask = 0; |
| } |
| rc = -EIO; |
| for (retry = 0; retry <= SCLP_MASK_RETRY; retry++) { |
| /* Prepare request */ |
| __sclp_make_init_req(receive_mask, send_mask); |
| spin_unlock_irqrestore(&sclp_lock, flags); |
| if (sclp_add_request(&sclp_init_req)) { |
| /* Try again later */ |
| wait = jiffies + SCLP_BUSY_INTERVAL * HZ; |
| while (time_before(jiffies, wait)) |
| sclp_sync_wait(); |
| spin_lock_irqsave(&sclp_lock, flags); |
| continue; |
| } |
| while (sclp_init_req.status != SCLP_REQ_DONE && |
| sclp_init_req.status != SCLP_REQ_FAILED) |
| sclp_sync_wait(); |
| spin_lock_irqsave(&sclp_lock, flags); |
| if (sclp_init_req.status == SCLP_REQ_DONE && |
| sccb->header.response_code == 0x20) { |
| /* Successful request */ |
| if (calculate) { |
| sclp_receive_mask = sccb->sclp_receive_mask; |
| sclp_send_mask = sccb->sclp_send_mask; |
| } else { |
| sclp_receive_mask = 0; |
| sclp_send_mask = 0; |
| } |
| spin_unlock_irqrestore(&sclp_lock, flags); |
| sclp_dispatch_state_change(); |
| spin_lock_irqsave(&sclp_lock, flags); |
| rc = 0; |
| break; |
| } |
| } |
| sclp_mask_state = sclp_mask_state_idle; |
| spin_unlock_irqrestore(&sclp_lock, flags); |
| return rc; |
| } |
| |
| /* Deactivate SCLP interface. On success, new requests will be rejected, |
| * events will no longer be dispatched. Return 0 on success, non-zero |
| * otherwise. */ |
| int |
| sclp_deactivate(void) |
| { |
| unsigned long flags; |
| int rc; |
| |
| spin_lock_irqsave(&sclp_lock, flags); |
| /* Deactivate can only be called when active */ |
| if (sclp_activation_state != sclp_activation_state_active) { |
| spin_unlock_irqrestore(&sclp_lock, flags); |
| return -EINVAL; |
| } |
| sclp_activation_state = sclp_activation_state_deactivating; |
| spin_unlock_irqrestore(&sclp_lock, flags); |
| rc = sclp_init_mask(0); |
| spin_lock_irqsave(&sclp_lock, flags); |
| if (rc == 0) |
| sclp_activation_state = sclp_activation_state_inactive; |
| else |
| sclp_activation_state = sclp_activation_state_active; |
| spin_unlock_irqrestore(&sclp_lock, flags); |
| return rc; |
| } |
| |
| EXPORT_SYMBOL(sclp_deactivate); |
| |
| /* Reactivate SCLP interface after sclp_deactivate. On success, new |
| * requests will be accepted, events will be dispatched again. Return 0 on |
| * success, non-zero otherwise. */ |
| int |
| sclp_reactivate(void) |
| { |
| unsigned long flags; |
| int rc; |
| |
| spin_lock_irqsave(&sclp_lock, flags); |
| /* Reactivate can only be called when inactive */ |
| if (sclp_activation_state != sclp_activation_state_inactive) { |
| spin_unlock_irqrestore(&sclp_lock, flags); |
| return -EINVAL; |
| } |
| sclp_activation_state = sclp_activation_state_activating; |
| spin_unlock_irqrestore(&sclp_lock, flags); |
| rc = sclp_init_mask(1); |
| spin_lock_irqsave(&sclp_lock, flags); |
| if (rc == 0) |
| sclp_activation_state = sclp_activation_state_active; |
| else |
| sclp_activation_state = sclp_activation_state_inactive; |
| spin_unlock_irqrestore(&sclp_lock, flags); |
| return rc; |
| } |
| |
| EXPORT_SYMBOL(sclp_reactivate); |
| |
| /* Handler for external interruption used during initialization. Modify |
| * request state to done. */ |
| static void sclp_check_handler(unsigned int ext_int_code, |
| unsigned int param32, unsigned long param64) |
| { |
| u32 finished_sccb; |
| |
| kstat_cpu(smp_processor_id()).irqs[EXTINT_SCP]++; |
| finished_sccb = param32 & 0xfffffff8; |
| /* Is this the interrupt we are waiting for? */ |
| if (finished_sccb == 0) |
| return; |
| if (finished_sccb != (u32) (addr_t) sclp_init_sccb) |
| panic("sclp: unsolicited interrupt for buffer at 0x%x\n", |
| finished_sccb); |
| spin_lock(&sclp_lock); |
| if (sclp_running_state == sclp_running_state_running) { |
| sclp_init_req.status = SCLP_REQ_DONE; |
| sclp_running_state = sclp_running_state_idle; |
| } |
| spin_unlock(&sclp_lock); |
| } |
| |
| /* Initial init mask request timed out. Modify request state to failed. */ |
| static void |
| sclp_check_timeout(unsigned long data) |
| { |
| unsigned long flags; |
| |
| spin_lock_irqsave(&sclp_lock, flags); |
| if (sclp_running_state == sclp_running_state_running) { |
| sclp_init_req.status = SCLP_REQ_FAILED; |
| sclp_running_state = sclp_running_state_idle; |
| } |
| spin_unlock_irqrestore(&sclp_lock, flags); |
| } |
| |
| /* Perform a check of the SCLP interface. Return zero if the interface is |
| * available and there are no pending requests from a previous instance. |
| * Return non-zero otherwise. */ |
| static int |
| sclp_check_interface(void) |
| { |
| struct init_sccb *sccb; |
| unsigned long flags; |
| int retry; |
| int rc; |
| |
| spin_lock_irqsave(&sclp_lock, flags); |
| /* Prepare init mask command */ |
| rc = register_early_external_interrupt(0x2401, sclp_check_handler, |
| &ext_int_info_hwc); |
| if (rc) { |
| spin_unlock_irqrestore(&sclp_lock, flags); |
| return rc; |
| } |
| for (retry = 0; retry <= SCLP_INIT_RETRY; retry++) { |
| __sclp_make_init_req(0, 0); |
| sccb = (struct init_sccb *) sclp_init_req.sccb; |
| rc = sclp_service_call(sclp_init_req.command, sccb); |
| if (rc == -EIO) |
| break; |
| sclp_init_req.status = SCLP_REQ_RUNNING; |
| sclp_running_state = sclp_running_state_running; |
| __sclp_set_request_timer(SCLP_RETRY_INTERVAL * HZ, |
| sclp_check_timeout, 0); |
| spin_unlock_irqrestore(&sclp_lock, flags); |
| /* Enable service-signal interruption - needs to happen |
| * with IRQs enabled. */ |
| ctl_set_bit(0, 9); |
| /* Wait for signal from interrupt or timeout */ |
| sclp_sync_wait(); |
| /* Disable service-signal interruption - needs to happen |
| * with IRQs enabled. */ |
| ctl_clear_bit(0,9); |
| spin_lock_irqsave(&sclp_lock, flags); |
| del_timer(&sclp_request_timer); |
| if (sclp_init_req.status == SCLP_REQ_DONE && |
| sccb->header.response_code == 0x20) { |
| rc = 0; |
| break; |
| } else |
| rc = -EBUSY; |
| } |
| unregister_early_external_interrupt(0x2401, sclp_check_handler, |
| &ext_int_info_hwc); |
| spin_unlock_irqrestore(&sclp_lock, flags); |
| return rc; |
| } |
| |
| /* Reboot event handler. Reset send and receive mask to prevent pending SCLP |
| * events from interfering with rebooted system. */ |
| static int |
| sclp_reboot_event(struct notifier_block *this, unsigned long event, void *ptr) |
| { |
| sclp_deactivate(); |
| return NOTIFY_DONE; |
| } |
| |
| static struct notifier_block sclp_reboot_notifier = { |
| .notifier_call = sclp_reboot_event |
| }; |
| |
| /* |
| * Suspend/resume SCLP notifier implementation |
| */ |
| |
| static void sclp_pm_event(enum sclp_pm_event sclp_pm_event, int rollback) |
| { |
| struct sclp_register *reg; |
| unsigned long flags; |
| |
| if (!rollback) { |
| spin_lock_irqsave(&sclp_lock, flags); |
| list_for_each_entry(reg, &sclp_reg_list, list) |
| reg->pm_event_posted = 0; |
| spin_unlock_irqrestore(&sclp_lock, flags); |
| } |
| do { |
| spin_lock_irqsave(&sclp_lock, flags); |
| list_for_each_entry(reg, &sclp_reg_list, list) { |
| if (rollback && reg->pm_event_posted) |
| goto found; |
| if (!rollback && !reg->pm_event_posted) |
| goto found; |
| } |
| spin_unlock_irqrestore(&sclp_lock, flags); |
| return; |
| found: |
| spin_unlock_irqrestore(&sclp_lock, flags); |
| if (reg->pm_event_fn) |
| reg->pm_event_fn(reg, sclp_pm_event); |
| reg->pm_event_posted = rollback ? 0 : 1; |
| } while (1); |
| } |
| |
| /* |
| * Susend/resume callbacks for platform device |
| */ |
| |
| static int sclp_freeze(struct device *dev) |
| { |
| unsigned long flags; |
| int rc; |
| |
| sclp_pm_event(SCLP_PM_EVENT_FREEZE, 0); |
| |
| spin_lock_irqsave(&sclp_lock, flags); |
| sclp_suspend_state = sclp_suspend_state_suspended; |
| spin_unlock_irqrestore(&sclp_lock, flags); |
| |
| /* Init supend data */ |
| memset(&sclp_suspend_req, 0, sizeof(sclp_suspend_req)); |
| sclp_suspend_req.callback = sclp_suspend_req_cb; |
| sclp_suspend_req.status = SCLP_REQ_FILLED; |
| init_completion(&sclp_request_queue_flushed); |
| |
| rc = sclp_add_request(&sclp_suspend_req); |
| if (rc == 0) |
| wait_for_completion(&sclp_request_queue_flushed); |
| else if (rc != -ENODATA) |
| goto fail_thaw; |
| |
| rc = sclp_deactivate(); |
| if (rc) |
| goto fail_thaw; |
| return 0; |
| |
| fail_thaw: |
| spin_lock_irqsave(&sclp_lock, flags); |
| sclp_suspend_state = sclp_suspend_state_running; |
| spin_unlock_irqrestore(&sclp_lock, flags); |
| sclp_pm_event(SCLP_PM_EVENT_THAW, 1); |
| return rc; |
| } |
| |
| static int sclp_undo_suspend(enum sclp_pm_event event) |
| { |
| unsigned long flags; |
| int rc; |
| |
| rc = sclp_reactivate(); |
| if (rc) |
| return rc; |
| |
| spin_lock_irqsave(&sclp_lock, flags); |
| sclp_suspend_state = sclp_suspend_state_running; |
| spin_unlock_irqrestore(&sclp_lock, flags); |
| |
| sclp_pm_event(event, 0); |
| return 0; |
| } |
| |
| static int sclp_thaw(struct device *dev) |
| { |
| return sclp_undo_suspend(SCLP_PM_EVENT_THAW); |
| } |
| |
| static int sclp_restore(struct device *dev) |
| { |
| return sclp_undo_suspend(SCLP_PM_EVENT_RESTORE); |
| } |
| |
| static const struct dev_pm_ops sclp_pm_ops = { |
| .freeze = sclp_freeze, |
| .thaw = sclp_thaw, |
| .restore = sclp_restore, |
| }; |
| |
| static struct platform_driver sclp_pdrv = { |
| .driver = { |
| .name = "sclp", |
| .owner = THIS_MODULE, |
| .pm = &sclp_pm_ops, |
| }, |
| }; |
| |
| static struct platform_device *sclp_pdev; |
| |
| /* Initialize SCLP driver. Return zero if driver is operational, non-zero |
| * otherwise. */ |
| static int |
| sclp_init(void) |
| { |
| unsigned long flags; |
| int rc = 0; |
| |
| spin_lock_irqsave(&sclp_lock, flags); |
| /* Check for previous or running initialization */ |
| if (sclp_init_state != sclp_init_state_uninitialized) |
| goto fail_unlock; |
| sclp_init_state = sclp_init_state_initializing; |
| /* Set up variables */ |
| INIT_LIST_HEAD(&sclp_req_queue); |
| INIT_LIST_HEAD(&sclp_reg_list); |
| list_add(&sclp_state_change_event.list, &sclp_reg_list); |
| init_timer(&sclp_request_timer); |
| /* Check interface */ |
| spin_unlock_irqrestore(&sclp_lock, flags); |
| rc = sclp_check_interface(); |
| spin_lock_irqsave(&sclp_lock, flags); |
| if (rc) |
| goto fail_init_state_uninitialized; |
| /* Register reboot handler */ |
| rc = register_reboot_notifier(&sclp_reboot_notifier); |
| if (rc) |
| goto fail_init_state_uninitialized; |
| /* Register interrupt handler */ |
| rc = register_early_external_interrupt(0x2401, sclp_interrupt_handler, |
| &ext_int_info_hwc); |
| if (rc) |
| goto fail_unregister_reboot_notifier; |
| sclp_init_state = sclp_init_state_initialized; |
| spin_unlock_irqrestore(&sclp_lock, flags); |
| /* Enable service-signal external interruption - needs to happen with |
| * IRQs enabled. */ |
| ctl_set_bit(0, 9); |
| sclp_init_mask(1); |
| return 0; |
| |
| fail_unregister_reboot_notifier: |
| unregister_reboot_notifier(&sclp_reboot_notifier); |
| fail_init_state_uninitialized: |
| sclp_init_state = sclp_init_state_uninitialized; |
| fail_unlock: |
| spin_unlock_irqrestore(&sclp_lock, flags); |
| return rc; |
| } |
| |
| /* |
| * SCLP panic notifier: If we are suspended, we thaw SCLP in order to be able |
| * to print the panic message. |
| */ |
| static int sclp_panic_notify(struct notifier_block *self, |
| unsigned long event, void *data) |
| { |
| if (sclp_suspend_state == sclp_suspend_state_suspended) |
| sclp_undo_suspend(SCLP_PM_EVENT_THAW); |
| return NOTIFY_OK; |
| } |
| |
| static struct notifier_block sclp_on_panic_nb = { |
| .notifier_call = sclp_panic_notify, |
| .priority = SCLP_PANIC_PRIO, |
| }; |
| |
| static __init int sclp_initcall(void) |
| { |
| int rc; |
| |
| rc = platform_driver_register(&sclp_pdrv); |
| if (rc) |
| return rc; |
| sclp_pdev = platform_device_register_simple("sclp", -1, NULL, 0); |
| rc = IS_ERR(sclp_pdev) ? PTR_ERR(sclp_pdev) : 0; |
| if (rc) |
| goto fail_platform_driver_unregister; |
| rc = atomic_notifier_chain_register(&panic_notifier_list, |
| &sclp_on_panic_nb); |
| if (rc) |
| goto fail_platform_device_unregister; |
| |
| return sclp_init(); |
| |
| fail_platform_device_unregister: |
| platform_device_unregister(sclp_pdev); |
| fail_platform_driver_unregister: |
| platform_driver_unregister(&sclp_pdrv); |
| return rc; |
| } |
| |
| arch_initcall(sclp_initcall); |